Interactive Truss Objects in Computer-Aided Design Models

1. A method for generating a truss object for a computer-aided design (CAD) model, the method comprising: receiving a selection of a truss family for the truss object, wherein the truss family specifies a plurality of components that include a top chord, a bottom chord, one or more vertical webs, and one or more diagonal webs, and, for each component, a geometry of the component and an arrangement of the component relative to a centerline axis; receiving a selection of a beginning point and an ending point within the CAD model at which to place the truss object, wherein the beginning point is coupled to a first object, and the ending point is coupled to a second object, and wherein the truss object is coupled to both the first object and the second object; determining, based on the selected truss family, the beginning point and the ending point, a centerline for a layout of the truss object that provides an axis for orienting the geometry of the truss object; generating a layout for the truss object based on the beginning point, the ending point and the centerline for the layout, wherein the layout defines a pattern for the truss object; generating a plurality of structural members to represent physical components of the truss object within the CAD model, wherein each structural member of the plurality of structural members corresponds to a different component specified by the truss family and is positioned within the CAD model according to the layout generated for the truss object and the geometry and the arrangement of the corresponding component specified by the truss family; associating the truss layout and the plurality of structural members with the truss object; storing the truss object in the CAD model; receiving an instruction to move the first object to a new position with respect to the second object; and modifying the truss object in accordance with the new position of the first object, to maintain the coupling of the truss object to both the first object and the second object.

2. The method of claim 1 , wherein the truss object is editable by a user of a CAD application, and wherein the editing of the truss object causes the CAD application to regenerate the layout and the plurality of structural members for the truss object to reflect the editing of the truss object.

3. The method of claim 1 , wherein the truss object is further associated with a set of instance properties, including a height, a length, a position, and an orientation of the truss object within the CAD model.

4. The method of claim 1 , wherein the truss family includes one or more properties for truss objects of that family, and wherein a modification to one of the properties causes a CAD application to modify any truss objects in the CAD model that were generated based upon that truss family to reflect the modification to one of the properties.

5. The method of claim 4 , wherein the one or more properties for the truss family include a height, a length, a position, and an orientation for truss objects generated according to that truss family.

6. The method of claim 1 , further comprising: receiving a selection of an object of the CAD model to which the truss object is to be attached; and creating an attachment between the truss object to the selected object, wherein the attachment is stored in the CAD model as an association between the truss object and the selected object of the CAD model.

7. The method of claim 6 , further comprising: receiving a modification to the selected object of the CAD model; and regenerating the layout and the plurality of structural members for the truss object to reflect the modification of the object of the CAD model attached to the truss object.

8. The method of claim 6 , wherein the selected object is a drawing object representing a roof, and wherein the step of attaching the truss object to the selected object comprises: modifying a top chord of the truss object to conform to a shape of the drawing object representing the roof; attaching the top chord to a bottom of the drawing object representing the roof; determining a centerline of the truss layout based on the modified top chord; generating a second truss layout to reflect the attachment to the drawing object representing the roof and a new centerline; and generating a second plurality of structural members of the truss object according to the new truss layout.

9. The method of claim 1 , wherein the plurality of structural members include drawing objects representing a top chord, a bottom chord, one or more vertical members and one or more diagonal members.

10. The method of claim 1 , wherein the instruction to move the first object to the new position is an instruction to move the first object closer to the second object and modifying the truss object further comprises changing the width of panels included in the truss object to maintain a specific number of panels.

11. A non-transitory computer-readable storage medium storing instructions that when executed by a processor cause the processor to generate a object for a computer-aided design (CAD) model by performing the steps of: receiving a selection of a truss family for the truss object, wherein the truss family specifies a plurality of components that include a top chord, a bottom chord, one or more vertical webs, and one or more diagonal webs, and for each component, a geometry of the component and an arrangement of the component relative to a centerline axis; receiving a selection of a beginning point and an ending point within the CAD model at which to place the object, wherein the beginning point is coupled to a first object, and the ending point is coupled to a second object, and wherein the truss object is coupled to both the first object and the second object; determining, based on the selected truss family, the beginning point, and the ending point, a centerline for a layout of the truss object that provides an axis for orienting the geometry of the truss object; generating a layout for the object based on the selected truss family, the beginning point, the ending point, and the centerline for the layout, wherein the layout defines a pattern for the object; generating a plurality of structural members to represent physical components within the CAD model, wherein the plurality of structural members are positioned within the CAD model, wherein each structural member of the plurality of structural members corresponds to a different component specified by the truss family and according to the layout generated for the object and the geometry and the arrangement of the corresponding component specified by the truss family; associating the layout and the plurality of structural members with the object; storing the object in the CAD model; receiving an instruction to move the first object to a new position with respect to the second object; and modifying the truss object in accordance with the new position of the first object, to maintain the coupling of the truss object to both the first object and the second object.

12. The non-transitory computer-readable storage medium of claim 11 , wherein the truss object is editable by a user of a CAD application, and wherein the editing of the truss object causes the CAD application to regenerate the layout and the plurality of structural members for the truss object to reflect the editing of the truss object.

13. The non-transitory computer-readable storage medium of claim 11 , wherein the truss object is further associated with a set of instance properties, including a height, a length, a position, and an orientation of the truss object within the CAD model.

14. The non-transitory computer-readable storage medium of claim 11 , wherein the truss family includes one or more properties for truss objects of that family, and wherein a modification to one of the properties causes a CAD application to modify any truss objects in the CAD model that were generated based upon that truss family to reflect the modification to one of the properties.

15. The non-transitory computer-readable storage medium of claim 14 , wherein the one or more properties for the truss family include a height, a length, a position, and an orientation for truss objects generated according to that truss family.

16. The non-transitory computer-readable storage medium of claim 11 , wherein the instructions further comprise instructions for: receiving a selection of an object of the CAD model; and creating an attachment between the truss object is to be attached to the selected object wherein the attachment is stored in the CAD model as an association between the truss object and the selected object of the CAD model.

17. The non-transitory computer-readable storage medium of claim 16 , wherein the instructions further comprise instructions for: receiving a modification to the selected object of the CAD model; and regenerating the layout and the plurality of structural members for the truss object to reflect the modification of the object of the CAD model attached to the truss object.

18. The non-transitory computer-readable storage medium of claim 16 , wherein the selected object is a drawing object representing a roof, and wherein the instructions for attaching the truss object to the selected object further comprise: modifying a top chord of the truss object to conform to a shape of the drawing object representing the roof; attaching the top chord to a bottom of the drawing object representing the roof; determining a centerline of the truss layout based on the modified top chord; generating a second truss layout to reflect the attachment to the drawing object representing the roof and a new centerline; and generating a second plurality of structural members of the truss object according to the new truss layout.

19. The non-transitory computer-readable storage medium of claim 11 , wherein the plurality of structural members include drawing objects representing a top chord, a bottom chord, one or more vertical members and one or more diagonal members.

20. A method for generating a truss object for a computer-aided design (CAD) model, the method comprising: selecting a truss family for the truss object, wherein the truss family specifies a plurality of components that include a top chord, a bottom chord, one or more vertical webs, and one or more diagonal webs, and, for each component, a geometry of the component and an arrangement of the component relative to a centerline axis; selecting a beginning point and an ending point within the CAD model at which to place the truss object, wherein the beginning point is coupled to a first object, and the ending point is coupled to a second object, and wherein the truss object is coupled to both the first object and the second object; invoking a truss creation tool provided by a CAD application, wherein the truss creation tool is configured to: determine, based on the selected truss family, the beginning point and the ending point, a centerline for a layout of the truss object that provides an axis for orienting the geometry of the truss object; generate a layout for the truss object based on the selected truss family, the beginning point, the ending point and the centerline for the layout, wherein the layout defines a pattern for the truss object; generate a plurality of structural members to represent physical components of the truss object within the CAD model, wherein each structural member of the plurality of structural members corresponds to a different component specified by the truss family and is positioned within the CAD model according to the layout generated for the truss object and the geometry and the arrangement of the corresponding component specified by the truss family; associate the truss layout and the plurality of structural members with the truss object; store the truss object in the CAD model; receive an instruction to move the first object to a new position with respect to the second object; and modify the truss object in accordance with the new position of the first object, to maintain the coupling of the truss object to both the first object and the second object.

21. The method of claim 20 , wherein the truss object is editable by a user of the CAD application, and wherein the editing of the truss object causes the CAD application to regenerate the layout and the plurality of structural members for the truss object to reflect the editing of the truss object.

22. The method of claim 20 , wherein the truss object is further associated with a set of instance properties, including a height, a length, a position, and an orientation of the truss object within the CAD model.

23. The method of claim 20 , wherein the truss family includes one or more properties for truss objects of that family, and wherein a modification to one of the properties causes the CAD application to modify any truss objects in the CAD model that were generated based upon that truss family to reflect the modification to one of the properties.

24. The method of claim 23 , wherein the one or more properties for the truss family include a height, a length, a position, and an orientation for truss objects generated according to that truss family.

25. The method of claim 20 , further comprising selecting an object of the CAD model to which the truss object is to be attached, and wherein the CAD application is further configured to create an attachment between the truss object to the selected object, wherein the attachment is stored in the CAD model as an association between the truss object and the selected object of the CAD model.

26. The method of claim 25 , further comprising: modifying the selected object of the CAD model, wherein the CAD application is further configured to regenerate the layout and the plurality of structural members for the truss object to reflect the modification of the object of the CAD model attached to the truss object.

27. The method of claim 25 , wherein the selected object is a drawing object representing a roof, and wherein the CAD application is further configured to: modify a top chord of the truss object to conform to a shape of the drawing object representing the roof; attach the top chord to a bottom of the drawing object representing the roof; determine a centerline of the truss layout based on the modified top chord; generate a second truss layout to reflect the attachment to the drawing object representing the roof and a new centerline; and generate a second plurality of structural members of the truss object according to the new truss layout.

28. The method of claim 20 , wherein the plurality of structural members include drawing objects representing a top chord, a bottom chord, one or more vertical members and one or more diagonal members.